Table 1.

Characteristics of the 22 animal model studies of distraction SCI included in this systematic review

Studies	Study design	Animal details	Number of animals	Characteristics				Outcome methods
				Neurophysiology	Biology	Behavior	Other
Shimizu et al., 2018	Controlled study	Long-Evans rats, adult, female	108	TcMEPs	Protein carbonyl content, VMN perikaryal size & VMN nuclear size	Gait analysis	Intraparenchymal pO2	h, hm, r, FM, N, Bt
Wu et al., 2017	Controlled study	Japanese white rabbits, male, 4–5 mon	40		Ink perfusion, corrosion casts, MDA, SOD			h, hm
Wu et al., 2016	Controlled study	Japanese white rabbits, male, 4–6 mon	32	CSEPs	Light microscopy, electron microscopy, MDA, SOD	Rivlin inclined plane test A, modified Tarlov scale		h, hm, N, Bt
Chen et al., 2016	Controlled study	Sprague-Dawley rats, male, 46 d	10		Spinal cord and spared tissue areas, myelinated axons density, surviving cells number	Martinez locomotor rating scale, FLAS, grooming test, grip strength test, Montoya staircase	Kinematics measurement	h, hm, FM, Bt, Bc
Hong et al., 2016	Observational study	Landrace and Yorkshire mixed pigs, 52.3 kg, young	13	TcMEPs	Structural changes, nerve sheath	Sensory evaluator kit, muscle strength, wake-up test	Vertebral height, disc height, segmental vertebral height length, thoracolumbar spinal length	h, r, Bt, N
Seifert et al., 2011	Controlled study	Long-Evans rats, female, 300 g	23	TcMEPs	Neuronal bodies, extent of tissue damage (astrocytes and macrophages)	BBB		h, hm, FM, N, Bt
Bell et al., 2017	Controlled study	Long-Evans rats, female, 300 g	60	TcMEPs	Evaluate tissue loss, number of neurons & VMN perikaryal size & VMN nuclear, protein carbonyl content	Dynamic plantar aesthesiometer (mechanoception), BBB	Intraparenchymal pO2	h, hm, FM, N, Bt
Choo et al., 2008	Controlled study	Sprague-Dawley rats, female, 347 g	33		Membrane permeability, oxidative stress in neuronal somata, inflammatory responses, axonal degeneration, axonal transport dysfunction, apoptosis			h, hm, FM
Wang et al., 2019	Controlled study	Sprague-Dawley rats, male, 280 g	23		Morphological characteristics, nucleus/cell body features, number of surviving cell			h, hm, FM
Qiu et al., 2015	Observational study	Goats, adult, 28 kg	11	SSEP		Tarlov grading score	Spinal cord volume, T10 height, disk height, osteotomy segment height, spinal segment height	r, MRI, N, Bt
Dolan et al., 1980	Controlled study	Mongrel cats, 3.4 kg	9	SER	Spinal cord blood flow			h, hm, r, N
Choo et al., 2009	Controlled study	Sprague-Dawley rats, 300 g, male	43		Hemorrhage, general morphology, large caliber axons, fine caliber axons, length between juxtaparanodal regions at the nodes of Ranvier		Mechanical injury parameters	h, hm, FM, Bc
Liu et al., 2004	Controlled study	Sprague-Dawley rats, adult, 205 g, either sex	40	CSEPs	Neuron section area, density of Nissl body, neuron count	Gale combined behavior score		h, hm, N, Bt
Liu et al., 2005	Controlled study	Sprague-Dawley rats, adult, 235 g	44	CSEPs	GFAP-positive cells	Gale combined behavior score		h, hm, N, Bt
Yang et al., 2013	Controlled study	Landrace and Yorkshire mixed breed, 3.3 mon, 51.6 kg	20	TcMEPs	Morphological changes in the axons and morphological changes in myelin sheath, general condition of the spinal cord (hemorrhage and inflammation)	Sensory evaluator kit, muscle strength, wake-up test	Vertebral height, disc height, segmental vertebral height length, thoracolumbar spinal length	h, r, Bt, N
Guo et al., 2019	Controlled study	Sprague-Dawley rats, 16 d, male	12		Spinal cord and spared tissue areas; myelinated axons density; surviving cells number	CatWalk system, ladder rung walking test		h, Bt
Skinner and Transfeldt, 2009	Observational study	Pigs, young adult	3	TcMEPs, EMG, ScMEPs				N
Jarzem et al., 1992	Observational study	Mix-breed dogs, 35 kg	5	SSEP	Cord tissue pressure, mean arterial pressure, spinal cord blood flow			h, N,
Kling et al., 1985	Observational study	Mongrel dogs, adult, 24.5 kg	13		Mean arterial pressure, spinal cord blood flow			R
Maiman et al., 1989	Controlled study	Conditioned cat	50	Evoked potentials	Histologic changes in gray and white matter	Modified Tarlov scale		h, N, Bt, r
Han et al., 2022	Controlled study	Experimental Bama pigs, 3 mon	9	ScMEPs	Histologic structure changes in gray and white matter, nerve fiber bundles structures	Modified Tarlov scale, muscle strength		h, hm, r, MRI, FM, Bt
Liang et al., 2022	Controlled study	Bama miniature pigs, 3 mon	9	ScMEPs	Histologic structure changes in gray and white matter, survival neuron count	Tarlov score, ILMS score		h, hm, Bt, FM

BBB: Basso, Beattie, Bresnahan locomotor rating scale; Bc: biomechanics; Bt: behavior test; CSEP: cortical somatosensory evoked potential; CSF: cerebrospinal fluid; CT: computed tomography; DSCI: distraction spinal cord injury; EMG: electromyography; FLAS: forelimb locomotor assessment scale; FM: fluorescence microscopy; GFAP: glial fibrillary acidic protein; h: histology; hm: histomorphometry; Iba-1: allograft inflammatory factor 1; IL: interleukin; ILMS: individual limb motor scale; MDA: malondialdehyde; MRI: magnetic esonance imaging; N: Neurophysiology; NeuN: neuronal nuclei; NF-κB P65: protein 65 of nuclear factor κB; p53: tumor protein P53; p-ERK: phosphorylated extracellular signal-regulated kinase; p-IκBα: phosphorylated nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha; p-JNK: phosphorylated c-Jun N-terminal kinase; p-P38: phosphorylated p38 mitogen-activated protein kinases; r: radiography; SCI: spinal cord injury; ScMEP: spinal cord motor evoked potential; SER: spinal evoked response; SOD: superoxide dismutase; SSEP: somatosensory evoked potential; TcMEP: transcranical motor evoked potential; TLR4: Toll-like receptor 4; TNF-α: tumor necrosis factor alpha; VMN: ventral motor neurons.